Electric-arc light.



E. A. SPERRY. ELECTRIC ARC LIGHT.

APPLICATION mm nov. 11. m4.

Patehtegl Apr. 29,1919.

[N VEN TOR. ELMER A. SPERRY' WITNESSExSi ATTOR EY BIKER A. SPEBBY, OI BROOKLYN NEW YORK.

ELECTRIC-ABC LIGHT.

Specification of mm rum.

Patented A r. 29, 1919.

Application filed November 11, 1914. Serial No. 871,488.

To all whom it may concern:

Be it known that I, ELMER A. SPERRY, a citizen-of the United States of America, residing at 100 Marlborough road, Brooklyn, New York, have invented certain new and useful Improvements in Electric-Arc Lights, of which the following is a specification.

This invention relates to are lights and has for its object to provide novel means for rotating, feeding, and supplying current to an electrode of a Searchlight.

The apparatus used in carrying my invention into effect may necessarily assume a variety of forms. The form as applied to searchlights which is now considered to be preferable is illustrated more or less diagrammatically in the accompanying drawings, in which Figure 1 is a view of the positive electrode holder, with the electrode in place.

Fig. 2 is a longitudinal section of the same.

Referring more in detail to the drawings, 1 represents an electrode, the axially extending aperture of which is shown at 2. The normal form ofcrater formed in actual operation is roughly shown at 2'. To provide for the unusual operating conditions of my light, I have devised a novel form of electrode holder, designed both to feed the carbon through the holder and to rotate it. Adjacent one end, the holder is provided with a rotatably mounted bevel gear 3, journaled on an extension 4 of the main body 5 of the holder. Said gear 3 is rotated by a "bevel pinion 6, journaled in fixed bearings within and without the arc lamp and rotated from any suitable source ofpower, represented by be t 7, at the desired s eed. Pivotally mounted on the face of sai bevel gear are a pair of brackets 8 and- 9 which are normally pulled toward each other by springs 10. These brackets carry feed rollers 11 and 12 for the carbon, the former being knurled or provided with teeth, while the latter is made in the form of a pair of separated disks 13 and 14, thus providing a three-point support for the carbon. The rollers are rotated by means of a worm wheel 15, mounted on the shaft of roller 12, and receiving its motion from worm 16. Motion ma be transmitted to roller 11 through gears 1; and 18, mounted on the shafts of rollers 11 and 12, respectively. The worm is journaled on extensions from bracket 9, and is provided with a star wheel 19, desi ed to engage an adjustable stop 20. Sai stop may be mountedadjace'nt pinion 6, and is preferably arranged to be automatically controlled by the relative position of the are light carbons. This may be accomplished by means of a solenoid 21, operated to withdraw the stop against the action of a spring 22, when the carbons approach each other too closely, as will be read- 1ly understood by those skilled inthe art.

The main body 5 of the holder is preferably corrugated as shown, to aid in the dissipation of heat. A plurality of spring pressed silver brushes 23 are provided to carry the main portion of the current into the carbon, with which they have sliding contact. A silver insert 24 may be provide opposite brushes 23 to keep the contacting surfaces in ood condition. The holder is preferably a so provided with an extension 25 of some highly refractory material, such as fire brick, 'alundum, nickel-steel, etc., designed to extend close to the arc itself and prevent the are spreading back on the outside of the carbon. This extension or cap 25 may be removably secured to the face of the holder as by means of bolts 25.

The mechanical operation of the structure shown upon the drawings is as follows:

Firstly, letit be understood that no attempt has been made to illustrate a complete Searchlight mechanism, no negative carbon or feeding mechanism therefore bein shown. For feeding the positive carbon have illustrated a special holder, designed to feed the carbon throu h the holder, so that very long carbon stic ma be employed. As the bevel r 6, whic forms in effect a base piece, 1s revolved it rotates the carbon 1 with it, through the gripping action of the spring pressed rollers 11 and 12. Gear 6 also carries with it the star wheel 19, which strikes stop 20 once each revolution and is rotated thereby so as to rotate the feed rollers on their own axes. The carbon is thus moved slowly forward, the rate of feeding bein governed by the automatic adjustment 0 the position of sto 20, as explained above. Thus the feed rol ers perform the double function of both rotating and feedi the carbon.

In accordance wit the provisions of the patent statutes, I have herein described the principle of operation of m invention, together with the apparatus which I now consider to represent the best embodiments thereof, but I desire to have it unde that the apparatus shown is only-illustrative and that the invention can be carried out b other means; Also, while it is designe to use the various features and elements in the combination and relations described some of these may be altered and others omitted without interfering with the more general results outlined, and the invention extends to such use.

Having now described my invention, what I claim and desire to secure by Letters Patent is:

1. In an arc lamp, an electrode holder comprising a base piece revolubly mounted concentrically with the electrode, a feed roller rotatably mounted on said base, means to rotate both the base and the roller on their respective axes, whereby the said roller transmits both a rotary and a translatory motion to the electrode, and means comprising a spring pressed brush for conveying electric current to the electrode and for imposing a frictional resistance to movement of the electrode through said holder.

2. An electrode holder for searchlights comprising a. body portion having an electrode receiving bore, a rotatable member mounted on said body portion, means for rotating said member, feeding means mounted on said member, means regulated independently from the rotation of said member but operated thereby, for actuating said feeding means whereby a constant rotation and regulatable feed of the electrode is secured, and a spring pressed current-conveying brush biased to a position in which it extends into said bore.

3. An electrode holder for searchlights comprising a body portion having an electrode-receiving bore, a rotatable member brush. for pressing the electrode laterally against-said holder.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses, this 30th day of October, 1914.

ELMER A. SPERRY.

Witnesses:

Annmr W. STRINGHAM, D. C. GOODMAN. 

